/**
 * All rights reserved. Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.jivesoftware.smackx.pubsub;

import java.util.Collections;
import java.util.Date;
import java.util.List;

/**
 * Represents an event generated by an item(s) being published to a node.
 * 
 * @author Robin Collier
 */
public class ItemPublishEvent<T extends Item> extends SubscriptionEvent {
	private List<T> items;
	private Date originalDate;

	/**
	 * Constructs an <tt>ItemPublishEvent</tt> with the provided list of
	 * {@link Item} that were published.
	 * 
	 * @param nodeId
	 *            The id of the node the event came from
	 * @param eventItems
	 *            The list of {@link Item} that were published
	 */
	public ItemPublishEvent(String nodeId, List<T> eventItems) {
		super(nodeId);
		items = eventItems;
	}

	/**
	 * Constructs an <tt>ItemPublishEvent</tt> with the provided list of
	 * {@link Item} that were published. The list of subscription ids represents
	 * the subscriptions that matched the event, in the case of the user having
	 * multiple subscriptions.
	 * 
	 * @param nodeId
	 *            The id of the node the event came from
	 * @param eventItems
	 *            The list of {@link Item} that were published
	 * @param subscriptionIds
	 *            The list of subscriptionIds
	 */
	public ItemPublishEvent(String nodeId, List<T> eventItems,
			List<String> subscriptionIds) {
		super(nodeId, subscriptionIds);
		items = eventItems;
	}

	/**
	 * Constructs an <tt>ItemPublishEvent</tt> with the provided list of
	 * {@link Item} that were published in the past. The published date
	 * signifies that this is delayed event. The list of subscription ids
	 * represents the subscriptions that matched the event, in the case of the
	 * user having multiple subscriptions.
	 * 
	 * @param nodeId
	 *            The id of the node the event came from
	 * @param eventItems
	 *            The list of {@link Item} that were published
	 * @param subscriptionIds
	 *            The list of subscriptionIds
	 * @param publishedDate
	 *            The original publishing date of the events
	 */
	public ItemPublishEvent(String nodeId, List<T> eventItems,
			List<String> subscriptionIds, Date publishedDate) {
		super(nodeId, subscriptionIds);
		items = eventItems;

		if (publishedDate != null)
			originalDate = publishedDate;
	}

	/**
	 * Get the list of {@link Item} that were published.
	 * 
	 * @return The list of published {@link Item}
	 */
	public List<T> getItems() {
		return Collections.unmodifiableList(items);
	}

	/**
	 * Indicates whether this event was delayed. That is, the items were
	 * published to the node at some time in the past. This will typically
	 * happen if there is an item already published to the node before a user
	 * subscribes to it. In this case, when the user subscribes, the server may
	 * send the last item published to the node with a delay date showing its
	 * time of original publication.
	 * 
	 * @return true if the items are delayed, false otherwise.
	 */
	public boolean isDelayed() {
		return (originalDate != null);
	}

	/**
	 * Gets the original date the items were published. This is only valid if
	 * {@link #isDelayed()} is true.
	 * 
	 * @return Date items were published if {@link #isDelayed()} is true, null
	 *         otherwise.
	 */
	public Date getPublishedDate() {
		return originalDate;
	}

	@Override
	public String toString() {
		return getClass().getName() + "  [subscriptions: " + getSubscriptions()
				+ "], [Delayed: "
				+ (isDelayed() ? originalDate.toString() : "false") + ']';
	}

}
